The US Navy has deployed a series of unmanned underwater vehicles (UUVs) to search for the Argentine Navy’s missing submarine, A.R.A. San Juan.

The vessel went missing in the South Atlantic waters with 44 personnel on-board last week, two days after its last communication with the navy, reported Reuters.

A.R.A. San Juan had departed from Ushuaia and was en route to the coastal city of Mar del Plata in the Buenos Aires province.

It is believed that the submarine encountered communication difficulties that could have resulted from an electrical outage.

"Naval spokesman Enrique Balbi said that the Argentine Navy submarine was last spotted and sent its final signal in the southern Argentine sea, 432km from the Patagonian coast."

Naval spokesman Enrique Balbi said that the Argentine Navy submarine was last spotted and sent its final signal in the southern Argentine sea, 432km from the Patagonian coast.

Balbi further added that a search-and-rescue procedure was initiated two days later after no visual or radar contact could be made with the vessel.

The US Navy fleet deployed for the task comprises one Bluefin-12D (Deep) UUV and three Iver 580 UUVs, which are operated by the navy’s recently established Unmanned Undersea Vehicle Squadron 1 based in Pearl Harbor, Hawaii.

Both of the autonomous vehicle variants are capable of being deployed rapidly and can survey wide areas of the ocean using side-scan sonar technology.

The Bluefin-12D UUV is able to carry out search and rescue operations at a travel speed of 3k and a maximum depth of almost 5,000ft for 30 hours at a time.

Iver 580 UUVs are capable of operating at a speed of 2.5k at a depth of 325ft for up to 14 hours.

The US Navy is also providing various rapid response capabilities such as aircraft, underwater equipment and personnel to aid the Argentine Navy in the search for its missing submarine.

A P-8A Poseidon aircraft has already been deployed by the US in Argentina, where the jet joined a NASA P-3 research aircraft to conduct an ongoing search in the region of the vessel’s last known location.

Mar del Plata naval base spokesman Gabriel Galeazzi said that the search team comprises 11 vessels from the Argentine Navy and various municipalities, as well as from other countries, reported CNN.

In addition to US, other nations participating in the search mission include Uruguay, Chile, Brazil, Peru and the UK.